How to Begin Implement Network Spectral Efficiency in NS3

To begin Network Spectral Efficiency using ns3, we can estimate the data rates that are sent through provided bandwidth in bits per second for each Hertz (bps/Hz). We can follow these steps to implement and analyze the Network Spectral Efficiency using NS3:

Steps to Begin Implement Network Spectral Efficiency in NS3

1. Understand Spectral Efficiency

Spectral efficiency is computed by:

Spectral Efficiency=Throughput (bps)Bandwidth (Hz)\text{Spectral Efficiency} = \frac{\text{Throughput (bps)}}{\text{Bandwidth (Hz)}}Spectral Efficiency=Bandwidth (Hz)Throughput (bps)​

• Throughput: Total data effectively sent in bits for each second.
• Bandwidth: Frequency range within Hertz that utilized for interaction.

Below are crucial aspects to impact the spectral efficiency:

• Modulation and coding schemes.
• Channel conditions such as noise, fading, interference.
• Multiple-access mechanisms like OFDM, CDMA, and MIMO.

2. Set Up Your Environment

We should install and download ns3 and working properly. Make acquainted with their appropriate modules like Wi-Fi, LTE, or 5G modules based on the needs.

3. Create a Network Topology

Example: Wireless Topology

NodeContainer nodes;

nodes.Create(2); // Create a transmitter and receiver

MobilityHelper mobility;

mobility.SetPositionAllocator(“ns3::GridPositionAllocator”,

“MinX”, DoubleValue(0.0),

“MinY”, DoubleValue(0.0),

“DeltaX”, DoubleValue(100.0),

“DeltaY”, DoubleValue(100.0),

“GridWidth”, UintegerValue(2),

“LayoutType”, StringValue(“RowFirst”));

mobility.SetMobilityModel(“ns3::ConstantPositionMobilityModel”);

mobility.Install(nodes);

YansWifiChannelHelper channel = YansWifiChannelHelper::Default();

YansWifiPhyHelper phy = YansWifiPhyHelper::Default();

phy.SetChannel(channel.Create());

WifiHelper wifi;

wifi.SetStandard(WIFI_PHY_STANDARD_80211n);

WifiMacHelper mac;

mac.SetType(“ns3::AdhocWifiMac”);

NetDeviceContainer devices = wifi.Install(phy, mac, nodes);

4. Set Up the Internet Stack

We can install the Internet stack that enabled for IP-based interaction:

InternetStackHelper stack;

stack.Install(nodes);

Ipv4AddressHelper address;

address.SetBase(“10.1.1.0”, “255.255.255.0”);

Ipv4InterfaceContainer interfaces = address.Assign(devices);

5. Generate Traffic

We should install applications to simulate the traffic for spectral efficiency analysis.

Example: UDP Traffic

UdpEchoServerHelper echoServer(9);

ApplicationContainer serverApps = echoServer.Install(nodes.Get(1)); // Receiver

serverApps.Start(Seconds(1.0));

serverApps.Stop(Seconds(10.0));

UdpEchoClientHelper echoClient(interfaces.GetAddress(1), 9);

echoClient.SetAttribute(“MaxPackets”, UintegerValue(1000));

echoClient.SetAttribute(“Interval”, TimeValue(Seconds(0.01))); // 10ms interval

echoClient.SetAttribute(“PacketSize”, UintegerValue(1024)); // 1KB packets

ApplicationContainer clientApps = echoClient.Install(nodes.Get(0)); // Transmitter

clientApps.Start(Seconds(2.0));

clientApps.Stop(Seconds(10.0));

6. Measure Throughput

During the simulation, monitor the data that are effectively sent.

FlowMonitor for Automated Throughput Measurement

FlowMonitorHelper flowmon;

Ptr<FlowMonitor> monitor = flowmon.InstallAll();

Simulator::Stop(Seconds(10.0));

Simulator::Run();

monitor->CheckForLostPackets();

Ptr<Ipv4FlowClassifier> classifier = DynamicCast<Ipv4FlowClassifier>(flowmon.GetClassifier());

std::map<FlowId, FlowMonitor::FlowStats> stats = monitor->GetFlowStats();

double totalThroughput = 0;

for (auto& flow : stats) {

double throughput = flow.second.rxBytes * 8.0 / (flow.second.timeLastRxPacket.GetSeconds() – flow.second.timeFirstTxPacket.GetSeconds()); // bps

totalThroughput += throughput;

std::cout << “Flow ” << flow.first << ” Throughput: ” << throughput / 1e6 << ” Mbps\n”;

}

7. Calculate Spectral Efficiency

Describe the bandwidth which is utilized for interaction like 20 MHz for Wi-Fi:

double bandwidth = 20e6; // 20 MHz

double spectralEfficiency = totalThroughput / bandwidth;

std::cout << “Spectral Efficiency: ” << spectralEfficiency << ” bps/Hz\n”;

8. Enable Tracing

Packet-Level Tracing

Record all packet events for detailed analysis:

AsciiTraceHelper ascii;

phy.EnableAsciiAll(ascii.CreateFileStream(“spectral_efficiency.tr”));

PCAP Tracing

Make PCAP tracing files for in-depth packet analysis:

phy.EnablePcapAll(“spectral_efficiency”);

9. Visualize Results

• Transfer throughput and spectral efficiency data into a file using external tools like MATLAB or Excel for graphical analysis.
• Envision the network using NetAnim:

AnimationInterface anim(“spectral_efficiency.xml”);

10. Experiment with Parameters

• Experiment with different modulation schemes such as BPSK, QPSK, 16-QAM.
• Replicate the diverse channel conditions like SNR, fading.
• Test with various bandwidths as 20 MHz, 40 MHz.

Example: Signify channel bandwidth for Wi-Fi module:

phy.Set(“ChannelWidth”, UintegerValue(20)); // 20 MHz

11. Run the Simulation

Execute the simulation and also examine the outcomes:

Simulator::Run();

Simulator::Destroy();

12. Advanced Scenarios

• MIMO Systems: Replicate the MIMO-based spectral efficiency using LTE module of NS3.
• OFDM: Mimic numerous sub-carriers for frequency-division multiplexing.
• 5G Networks: For advanced spectral efficiency analysis, we need to leverage 5G NR module of NS3.

We shared a comprehensive procedure for Network Spectral Efficiency that were implemented and analyzed using NS3 simulation tool and we are ready to provide additional advanced insights based on your requirements.